Last updated: November 9, 2023

Summarytoggle arrow icon

Migraine is a primary headache characterized by recurrent episodes of unilateral, localized pain that are frequently accompanied by nausea, vomiting, and sensitivity to light and sound. In approximately 25% of cases, patients experience an aura preceding the headache, which involves reversible focal neurological abnormalities, e.g., visual field defects (scotomas) or paresis lasting less than an hour. Migraine is a clinical diagnosis and imaging is generally not indicated. Treatment of attacks consists of general measures (e.g., minimizing light and sound) together with administration of nonsteroidal antiinflammatory drugs (e.g., aspirin) and antiemetics (e.g., prochlorperazine) if nausea is present. In severe cases, triptans may be added. Prophylactic treatment (e.g., beta blockers) may be indicated if migraines are especially frequent or long-lasting, or if abortive therapy fails or is contraindicated.

Epidemiologytoggle arrow icon

  • Prevalence: ∼ 17% of females and ∼ 6% of males [1]
  • Peak incidence: 30–39 years [2][3]
  • Migraine is the second most common type of headache.

Among patients presenting to the emergency department with a headache, migraine is the most common cause. [4]

Epidemiological data refers to the US, unless otherwise specified.

Etiologytoggle arrow icon

Pathophysiologytoggle arrow icon

Vasodilatation is now considered an epiphenomenon rather than the primary cause of migraine headache. [6]

Clinical featurestoggle arrow icon

Migraine is characterized by recurrent attacks and may occur with aura (∼ 25% of cases) or without aura (∼ 75% of cases). A typical migraine attack passes through four stages, and the aura (if present) typically occurs before the headache. However, migraine patterns may differ and not follow the characteristic stages.

1. Prodrome (facultative)

  • 24–48 hours before the headache starts
  • Excessive yawning
  • Difficulties with writing or reading
  • Sudden hunger or lack of appetite
  • Mood changes

2. Aura

Paroxysmal, focal, neurological symptoms that precede (or, in some cases, occur during) the headache.

Typical aura [9][10]

  • Visual disturbances, sensory and/or speech symptoms (positive ; and/or negative ;)
    • Scintillating scotoma: an arch-shaped scotoma that starts centrally and shifts peripherally (appears for ∼ 15–30 minutes)
    • Central scotoma
    • Flashing lights
    • Distorted color perception
    • Fortification spectra: star-like, zigzag figures
    • Sensory deficits, paresthesia
    • Aphasia
  • No motor symptoms
  • Develops gradually
  • Completely reversible
  • Symptoms last ≤ 60 minutes each

Atypical aura

3. Headache

  • Localization
    • Typically unilateral, but bilateral headache is possible
    • Especially frontal, frontotemporal, retro-orbital
  • Duration: usually 4–24 hours (rarely over 72 hours)
  • Course: progression of pulsating, throbbing, or pounding pain
  • Exacerbated by physical activity
  • Accompanying symptoms: photophobia, phonophobia, and nausea/vomiting

4. Postdrome (facultative)

  • Feeling of exhaustion or euphoria
  • Muscle weakness
  • Anorexia or food cravings

The typical migraine headache is “POUND”: Pulsatile, One-day duration, Unilateral, Nausea, Disabling intensity.

Subtypes and variantstoggle arrow icon

All variants of acute migraine should raise suspicion for other diagnoses (e.g., transient ischemic attack), especially if the first aura occurs after 40 years of age, auras last an atypical amount of time, or symptoms are predominantly negative.

Migraine with brainstem aura [9]

Vestibular migraine [9][11]

  • Most common cause of spontaneous episodic vertigo
  • Diagnosed migraine plus ≥ 5 episodes of vestibular symptoms (e.g., vertigo) lasting ≤ 72 hours
  • Treatment may be complemented with antivertigo agents (e.g., dimenhydrinate ).

Hemiplegic migraine [9]

  • May be familial or sporadic
  • Main differential diagnosis: epilepsy
  • Fully reversible aura (lasts ∼ 72 hours) consisting of both motor weakness and visual, sensory, or speech impairment

Retinal migraine [9]

  • Aura consists of monocular visual phenomena (e.g., scintillation, scotoma, blindness).
  • All symptoms are fully reversible.
  • Aura fulfills ≥ 2 of the following criteria:
    • Spread: gradually over ≥ 5 minutes
    • Duration: 5–60 minutes
    • Onset of headache: within 60 minutes

Typical aura without headache (silent migraine) [9]

  • Aura symptoms are present.
  • Aura lasts for ≥ 60 minutes before the onset of the headache, which might not develop at all.
  • Episodes may coexist with typical migraine symptoms.

Chronic migraine [9]

  • Patients with migraine diagnosis (with or without aura) presenting with a ≥ 3-month history of the following:
    • Headaches (variable in intensity and type ) ≥ 15 days/month
    • ≥ 8 days/month headache has migraine characteristics or is relieved by migraine-specific medication (triptans, ergotamine).
  • A headache diary is recommended for patients to help optimize treatment.
  • Main differential diagnosis: medication overuse headache

Diagnosticstoggle arrow icon

Migraine is a clinical diagnosis based on history and physical examination. The most important step is to exclude red flags for headache that suggest a secondary headache (e.g., infection, hemorrhage, intracranial mass) and require more exhaustive investigation (e.g., imaging). Suspect a primary headache when no red flags are identified, and confirm the diagnosis using the diagnostic criteria for migraine. [9][12]

Migraine is a clinical diagnosis that is based on patient history and physical examination.

Diagnostic criteria

Diagnostic criteria for migraine [9][13]
Migraine without aura Migraine with aura
Number of attacks (total lifetime)
  • ≥ 5
  • ≥ 2
  • 4–72 hours
  • N/a
  • ≥ 2 of the following:
    • Unilateral
    • Pulsating
    • Moderate or severe pain
    • Worsened by routine physical activity
  • ≥ 1 of the following aura symptoms:
    • Visual
    • Sensory
    • Speech
    • Motor
    • Brainstem
    • Retinal
  • ≥ 3 of the following aura characteristics:
    • ≥ 1 spreads gradually over ≥ 5 minutes.
    • ≥ 2 occur in succession.
    • Each one lasts 5–60 minutes.
    • ≥ 1 is unilateral.
    • ≥ 1 involves a positive symptom.
    • Accompanied or followed by headache (within 60 minutes)

Avoid anchoring bias in patients with known migraines and pursue a diagnostic workup for headache in patients with red flags for headache.

Laboratory studies

  • Not routinely indicated
  • Consider a urine pregnancy test to guide pharmacotherapy choices in women of childbearing age.

Imaging [12][14][15]

Neurological imaging is not routinely indicated for uncomplicated migraine.

Avoid imaging in patients presenting with a recurrent known migraine unless new concerning features are present, e.g., seizures, focal neurological deficits, or recent change in headache pattern.

Differential diagnosestoggle arrow icon

The differential diagnoses listed here are not exhaustive.

Treatmenttoggle arrow icon

See “Migraine management in pregnancy” for abortive and preventative agents that are safe for pregnant individuals. The following recommendations are consistent with American Headache Society (AHS) guidelines. [16][17][18][19]

Abortive therapy for migraines [13][19][20]

All patients

Avoid opioids as first-line treatment for acute migraines, given their unclear efficacy and potential harm (e.g., worse nausea and vomiting). [16][21]

Mild to moderate headache [9][16]

Moderate to severe headache [9][16][21]

Trial a parenteral antidopaminergic agent OR start a migraine-specific agent.

Parenteral antidopaminergics (i.e., IV metoclopramide or IV prochlorperazine) are effective first-line agents for migraine regardless of GI symptoms or ability to tolerate oral medication.

In the emergency department, consider IV dexamethasone to reduce the risk of recurrent migraine after discharge. [16]

Overview of migraine-specific agents

Migraine-specific agents


  • Sumatriptan, zolmitriptan, almotriptan, rizatriptan
Mechanism of action
Side effects

Remember to check for drug interactions (e.g., with SSRIs or macrolides) before starting triptans or ergotamines to avoid adverse events. Coronary spasm and/or serotonin syndrome can occur if triptans and ergotamines are combined.

Ergotamines are contraindicated in pregnancy. [25]

A SUMo wrestler TRIPs ANd falls on his head: SUMaTRIPtANs are used for headaches (cluster and migraine).

Prophylactic therapy of migraine

Nonpharmacological [26]

  • Lifestyle modifications
    • Exercise in moderation
    • Maintain a healthy diet
    • Identify and try to avoid potential triggers
    • Follow a regular sleeping schedule
  • Other: There is some evidence that the following nonpharmacological interventions have some benefits for patients with migraine

Pharmacological [28]

Complicationstoggle arrow icon

Status migrainosus [9]

  • Description: Debilitating migraine attack in a patient with a known migraine diagnosis (with or without aura)
    • Exceptional in duration (≥ 72 hours) and severity
    • Often related to medication overuse
  • Treatment: stepwise therapy with reassessment between drug administration [33]

We list the most important complications. The selection is not exhaustive.

Acute management checklisttoggle arrow icon

Dispositiontoggle arrow icon

Special patient groupstoggle arrow icon

Management of migraine in pregnancy [25][39]

Abortive therapies

Prophylactic therapy

Migraine in children [40][41]

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Referencestoggle arrow icon

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